package com.sky.service.impl;


import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.time.LocalDateTime;
import java.util.List;

@Slf4j
@Service
public class ShoppingCartServiceImpl implements ShoppingCartService {

    private static final Integer INITIAL_NUMBER = 1;

    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetmealMapper setmealMapper;

    @Override
    public void add(ShoppingCartDTO shoppingCartDTO) {
        //判断商品是否已经存在,使用user_id和setmeal_id字段来查询
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        shoppingCart.setUserId(BaseContext.getCurrentId());
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);//这里只会返回一条数据,是为了数据复用

        //如果存在,数量+1
        if (list != null && !list.isEmpty()) {
            ShoppingCart cart = list.get(0);
            Integer num = cart.getNumber();
            cart.setNumber(num+1);
            shoppingCartMapper.updateById(cart);
        }else{//如果不存在,在表内新增
            //判断本次添加进购物车的是菜品还是套餐
            Long dishId = shoppingCartDTO.getDishId();
            Long setmealId = shoppingCartDTO.getSetmealId();
            if (dishId != null) {
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setImage(dish.getImage());
                shoppingCart.setAmount(dish.getPrice());
            }else{
                Setmeal setmeal = setmealMapper.getSetmealById(setmealId);
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(INITIAL_NUMBER);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.add(shoppingCart);

        }
    }

    @Override
    public List<ShoppingCart> list() {
        Long userId = BaseContext.getCurrentId();//获取当前微信用户的id
        ShoppingCart shoppingCart = new ShoppingCart();
        shoppingCart.setUserId(userId);
        return shoppingCartMapper.list(shoppingCart);
    }

    @Override
    public void clean() {
        Long userId = BaseContext.getCurrentId();
        shoppingCartMapper.clean(userId);
    }

    @Override
    @Transactional
    public void deleteOne(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        //设置查询条件，查询当前登录用户的购物车数据
        shoppingCart.setUserId(BaseContext.getCurrentId());

        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        if(list != null && !list.isEmpty()){
            shoppingCart = list.get(0);

            Integer number = shoppingCart.getNumber();
            if(number == 1){
                //当前商品在购物车中的份数为1，直接删除当前记录
                shoppingCartMapper.deleteById(shoppingCart.getId());
            }else {
                //当前商品在购物车中的份数不为1，修改份数即可
                shoppingCart.setNumber(shoppingCart.getNumber() - 1);
                shoppingCartMapper.updateById(shoppingCart);
            }


        }
    }
}
